You have this structure in your code: 
while my $text=<$testo>){
    ...
    $count += () = /\b$key\b/ig while <>;
}

[download]

The <> file handle is exhausted in the first run of the outer while loop, thus certainly not doing what you want. Why do you read from <> at all? Doesn't $text already contain an input line?

In reply to Re: Counting occurence of a list of word in a file by moritz
in thread Counting occurence of a list of word in a file by b_vulnerability

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